diff --git a/Lib/importlib/_bootstrap.py b/Lib/importlib/_bootstrap.py
--- a/Lib/importlib/_bootstrap.py
+++ b/Lib/importlib/_bootstrap.py
@@ -1606,7 +1606,7 @@ def _get_supported_file_loaders():
     return [extensions, source, bytecode]
 
 
-def __import__(name, globals={}, locals={}, fromlist=[], level=0):
+def __import__(name, globals=None, locals=None, fromlist=(), level=0):
     """Import a module.
 
     The 'globals' argument is used to infer where the import is occuring from
@@ -1617,6 +1617,8 @@ def __import__(name, globals={}, locals=
     import (e.g. ``from ..pkg import mod`` would have a 'level' of 2).
 
     """
+    globals = globals or {}
+    locals = locals or {}
     if level == 0:
         module = _gcd_import(name)
     else: